This invention relates to electroluminescent lamps, which typically are formed of a phosphor-particle-containing layer disposed between corresponding electrodes adapted to apply an excitation potential to the phosphor particles, at least one of the electrode layers being semi-transparent to light emitted by the phosphors
The phosphor-containing layer is provided with a barrier against moisture penetration to prevent premature deterioration of the phosphors, and permanent adherence between adjacent layers is sought to avoid delamination, e.g. under constant flexing or changes in temperature, particularly where the layers are of materials having different physical properties as this can also lead to premature failure in prior art electroluminescent lamps.
In one major application, i.e. for lighting membrane keyboards, the layers of the lamp and the supporting substrate must be flexible.